From patchwork Wed Jun 16 13:38:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Georgi Djakov X-Patchwork-Id: 12325233 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A8A30C48BE6 for ; Wed, 16 Jun 2021 13:41:58 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 76FD160FE8 for ; Wed, 16 Jun 2021 13:41:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 76FD160FE8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=quicinc.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=tczY01Q8FejOJEcSRYxmEzyVvZtfD5CmwIwr3v99gZI=; b=eAaZCc53HEnZzc 4QXmN9WuPwytMvAY9sGV4sBcRIGQimvcIHzI14WmOwvp8UKkLGWTXFDmNwLySsqKCg5BoxSoILBoZ SCjleFiMGJtbUIJdAjg0KzkINx1r394e90RBeNcQulWG+G3vGYNuR5HJpyq7HZ7b2Fe3PyhhDfQSQ M6f1dXiP2PTTZWiD/VuJyRKR46ZEDHoGyL3f6dP8wYvtR3l/de9vhFKVZezo88Fq3QwsSgHCc/HIr G0+GJGcb/cuLZwIQAAul2cqsbINVrDqUccvBzYf2WT/axIvpMw3JsAwIBFrxBUUJHHM2bXWb1oHaJ 391IgQwfUcJjhck4TesQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ltVlT-006SlF-OQ; Wed, 16 Jun 2021 13:39:31 +0000 Received: from alexa-out-sd-02.qualcomm.com ([199.106.114.39]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ltVlF-006Sjf-3i for linux-arm-kernel@lists.infradead.org; Wed, 16 Jun 2021 13:39:18 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1623850757; x=1655386757; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version; bh=H6YXXaA72lhIwfvaqkBYUyVRVQLeQOAd+Giz9XXvNpA=; b=qVY2B0jOZZe7zm/3oKN95MzOLPIeF4bMNp6mX7CakvuB6VGaIS14ewxy 5enObk4yGB2S2jwIQoq33Y4E6kydn+yvGGyijjjIA+VnG5jq+1L3sG3My XWDyDeHRVxuU+db+3xwngAT4KjD+meaTe2HzrSdcfF+rQY1Ug6UBlhYzZ g=; Received: from unknown (HELO ironmsg04-sd.qualcomm.com) ([10.53.140.144]) by alexa-out-sd-02.qualcomm.com with ESMTP; 16 Jun 2021 06:39:16 -0700 X-QCInternal: smtphost Received: from nasanexm03e.na.qualcomm.com ([10.85.0.48]) by ironmsg04-sd.qualcomm.com with ESMTP/TLS/AES256-SHA; 16 Jun 2021 06:39:09 -0700 Received: from th-lint-040.qualcomm.com (10.80.80.8) by nasanexm03e.na.qualcomm.com (10.85.0.48) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Wed, 16 Jun 2021 06:39:07 -0700 From: Georgi Djakov To: , CC: , , , , , , , Subject: [PATCH v7 05/15] iommu: Use bitmap to calculate page size in iommu_pgsize() Date: Wed, 16 Jun 2021 06:38:46 -0700 Message-ID: <1623850736-389584-6-git-send-email-quic_c_gdjako@quicinc.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1623850736-389584-1-git-send-email-quic_c_gdjako@quicinc.com> References: <1623850736-389584-1-git-send-email-quic_c_gdjako@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanexm03h.na.qualcomm.com (10.85.0.50) To nasanexm03e.na.qualcomm.com (10.85.0.48) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210616_063917_222979_31D9F9B3 X-CRM114-Status: GOOD ( 14.84 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Will Deacon Avoid the potential for shifting values by amounts greater than the width of their type by using a bitmap to compute page size in iommu_pgsize(). Signed-off-by: Will Deacon Signed-off-by: Isaac J. Manjarres Signed-off-by: Georgi Djakov Reviewed-by: Lu Baolu --- drivers/iommu/iommu.c | 31 ++++++++++++------------------- 1 file changed, 12 insertions(+), 19 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 5419c4b9f27a..80e471ada358 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -8,6 +8,7 @@ #include #include +#include #include #include #include @@ -2378,30 +2379,22 @@ static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long addr_merge, size_t size) { unsigned int pgsize_idx; + unsigned long pgsizes; size_t pgsize; - /* Max page size that still fits into 'size' */ - pgsize_idx = __fls(size); + /* Page sizes supported by the hardware and small enough for @size */ + pgsizes = domain->pgsize_bitmap & GENMASK(__fls(size), 0); - /* need to consider alignment requirements ? */ - if (likely(addr_merge)) { - /* Max page size allowed by address */ - unsigned int align_pgsize_idx = __ffs(addr_merge); - pgsize_idx = min(pgsize_idx, align_pgsize_idx); - } - - /* build a mask of acceptable page sizes */ - pgsize = (1UL << (pgsize_idx + 1)) - 1; - - /* throw away page sizes not supported by the hardware */ - pgsize &= domain->pgsize_bitmap; + /* Constrain the page sizes further based on the maximum alignment */ + if (likely(addr_merge)) + pgsizes &= GENMASK(__ffs(addr_merge), 0); - /* make sure we're still sane */ - BUG_ON(!pgsize); + /* Make sure we have at least one suitable page size */ + BUG_ON(!pgsizes); - /* pick the biggest page */ - pgsize_idx = __fls(pgsize); - pgsize = 1UL << pgsize_idx; + /* Pick the biggest page size remaining */ + pgsize_idx = __fls(pgsizes); + pgsize = BIT(pgsize_idx); return pgsize; }